Linear drives in drilling sleeves, with which the linear feed motion of the drilling tools is realized, are generally embodied by means of combinations of toothed rack and pinion driven by electric motor. Such drilling sleeves have the disadvantage of relatively large external dimensions. Alternatively, hydraulic or pneumatic linear drives for drilling sleeves are also known, which are, however, relatively effort-intensive as a result of the necessary provision of a hydraulic or pneumatic energy source, and also in design terms.